Usually I leave it plugged in overnight anyway, but sometimes I forget. Usually, it may go down maybe 5% or 10% during the night, if I forget to plug it in. But every so often, like last night, it was nearly fully charged when I went to sleep and then completely dead when I woke up.
What’s up with that? And why does it only happen once in a while?
I used to often go into places with spotty cell phone coverage. And even without using the phone once the whole day, it would often die before the day was done. While in town, it seemed fine. Some other reported similiar problems.
Our theory was that the phone “trying” to maintain coverage and or switching towers often was what was draining the batteries.
Maybe you have borderline coverage that is good enough most nights, but not all nights.
From my experience on a tour of duty as the power management lead for a cell phone, I’d say there are two main things that cause big battery drops:
Marginal coverage causing lots of scanning for service or higher broadcast power. This seems unlikely, if you leave the phone in relatively the same place.
Run-away applications. Sometimes this will include something that prevents the display from turning off, making it even worse.
Modern Android phones have a monitor that shows what applications used what percentage of CPU use. Most other smart phones probably have a similar list.
ETA: Just saw your comment about having poor coverage. That would explain it - it’s possible that you have an obstruction somewhere that drops coverage even more than normal, and if the
phone is in certain locations, it suffers from that.
I work in a facility that’s shielded (from Verizon, at least), and my phone will die in one work day if I leave it on at my desk. It’s become an emergency phone, mostly–I leave it off and check for messages at the end of the day.
Starting in 2013, out of the blue, my wife’s eye phone started having issues with the battery going dead within a matter of a few hours. After trying a number of things, including phoning Apple and dealing with their “how lucky you are to have one of our products” type attitude, we finally sent it back to them and she got a new one on warranty. Same problem. It appeared to be at least in major part being caused when it was connected to email.
About 6 months ago she bought a fancy pants new eye phone and it also would go dead in fairly short order so she cannot have it connected to email either.
I think it must just be the nature of some of these phones. My Blackberry which of course doesn’t have nearly as many gadgets, doesn’t have that problem.
I think it’s just a matter of some devices are prone to the battery going dead quicker than others and that’s probably just the way it is.
You’ll want to compare the battery usage from a ‘good’ night and a ‘bad’ night to see if it’s different. If the ‘bad’ night is what is showing “Cell Standby - 93%”, then we can be fairly sure it’s a coverage issue.
seriously, I’ve never had an Android phone which had anything resembling acceptable battery life. Android seems far too permissive in letting apps run in the background and torch the battery. the last one I had was a Nexus 5 and its battery life was criminally bad. I’d often find that apps I hadn’t even used that day had fired up in the background and used a ton of battery. When I could feel the phone getting warm in my pocket, I knew there was a problem.
also it seems like a lot of these phones are programmed to crank up the radio power to try to hang on to an LTE signal when it would just be better to fall back to 3G.